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Stem Cells Liver Disease
The human liver is a highly resilient organ with amazing regenerative abilities. Unfortunately for a number of reasons it can break down over time, and although there are a number of different treatments available for complete liver failure a transplant is the only option – and this can be a risky business at best. Although not even a full liver is necessary to be transplanted from one individual to another in order for treatment to be successful (given that even if 40% of the original liver is transplanted into a patient the liver’s natural generation ability will cause it to re-grow to roughly the original size) the chances of organ rejection are still high and a major concern for many people suffering from liver disease. Additionally the widespread epidemic of liver failure means that for every one successful liver transplant 10 people are left on the waiting list hoping to receive one of their own.
Because of the risk of organ rejection among other concerns (including simply finding a suitable donor quick enough to save the life of an individual) alternative treatments utilizing adult stem cell therapy has been explored. In fact, researchers in both London and Japan are currently exploring treatment methods utilizing adult stem cells for the treatment of chronic liver disease and liver fibrosis.
This move towards liver repair and exploration of stem cell therapy to repair liver damage is partly due to the fact that there is a lack of any significant dialysis machine to assist with the liver’s functions (unlike dialysis for kidney failure), making the need for a treatment method other than an invasive transplant dire. Additionally studies have shown that liver disease is on the rise in many countries around the world, with highly-industrialized countries such as the UK and US among two of the homes of the fastest growing liver-disease demographic in the world.
The stem cells being used in the treatments underway in the UK and Japan are being extracted from the patient’s own bone marrow, effectively eliminating the risk of rejection from the patient as the cells will simply be modified native cells to the patient’s body. Adult stem cells extracted from bone marrow are proving highly flexible for use in many different areas of treatment, ranging anywhere from tissue repair (such as that being done in these cases in regards to liver damage) to even being utilized in the treatment of traumatic brain injury cases.
Subscribe to the comments for this postStem Cells Knee Repair
Knee cartilage is a highly resilient tissue that is necessary to absorb high amounts of stress throughout our lives on a regular basis, needing the ability to withstand heavy loads and impacts that we subject our body to through any number of actions. Unfortunately it is also a non-regenerative tissue and if damaged or worn-down through years of hard usage or other complications such as disease or nutritional deficiency it can easily cause a wide number of problems and, in extreme situations, even cause immobility.
While a number of surgical options have been available for some time in order to assist with mending cartilage tissue damage there has been no way to actually repair any cartilage damage to its proper complete state. Further, while some of these surgical options can be done arthriscopically (by making small 1cm incisions in the areas surrounding the knee and inserting small instruments into the knee cavity to conduct repairs) more extreme damage requires highly invasive procedures that can take months to recover from and after which individuals may never fully recover to their pre-damaged level of use.
Recent developments in autologus stem cells, however, are proving promising in terms of being able to regenerate damaged cartilage tissue. Originating from a patient’s own body, autologus cells have virtually no risk of be rejected by the patient as they are simply modifications of cells already existing within their system. Further, there is no risk of any disease transmission through the use of autologus cells due to the fact that they do not come into contact with any outside source. Their nature also allows them to be more easily studied and implemented in treatment procedures due to the fact that they are harvested from and re-implanted in adult bodies and therefore are free of much of the negative stigma associated with other forms of stem cells.
Current focus for stem cell cartilage treatment is on the usage of autologus mesenchymal stem cells due to their promising results in animal studies. A clinic in Colorado has also reported numerous successes in the usage of autologus mesenchymal stem cells to regenerate knee tissue in many patients. Unfortunately due to the relatively new nature of the treatments as well as the limited ability to know of long-term effects of the stem cell treatments the FDA is engaged in an ongoing debate over their continued usage within the US and whether or not they are truly a viable, healthy method of treatment.
Stem Cells Brain Damage
Traumatic brain injury (commonly known as TBI) is a primary candidate for stem cell study and treatment due primarily to two factors. First, the current conventional treatment methods used in TBI cases focus primarily on pharmacological supplements to bring about balances in brain chemistry that may have been imbalanced due to trauma as well as rehabilitation treatments to allow an individual to better cope with lost functionality that may have come about due to the initial brain injury or, more likely, the subsequent swelling that results from the body’s natural defense mechanism to deal with traumas. While this has proven effective in coping with brain damage in the past it is inherently limited in its actual scope of application due to the fact that it does not ever treat the actual damage that exists. Secondly, TBI has proven as a prime candidate for stem cell research and development due to the fact that various stem cells were recently discovered in adult brains that, when activated, could effectively be used to repair damaged brain tissue and return lost functionality to otherwise unusable brain regions. Additionally some bone marrow stem cells have proven effective in generating the necessary cells to repair damage to areas that have recently suffered from some sort of trauma based on laboratory studies. In fact, if modified adult stem cells from bone marrow is injected into damaged regions of the brain within 48 hours of an injury occurring significant recovery of damaged tissue has been able to be observed in laboratory animal tests. Because of the high potential nature of adult stem cells in the treatment of traumatic brain injury tests are currently being planned on the first human subjects, with the intention of treating children suffering from TBI at first with bone marrow extracted from their pelvis. These stem cells will be activated to restore both neurological tissue and blood flow to damaged regions in order to stem off any cumulative damage that may result from otherwise untreatable areas. Due to the fact that TBI is currently the leading cause of death for individuals under the age of 45 within the United States as well as a highly debilitating condition with little to no current effective treatment in place these initial tests are being highly anticipated by a number of parties and could help pave the way for future breakthroughs in stem cell usage for brain trauma treatment in the coming years.
Stem Cell Potency
Much like virtually all drugs stem cells are also attributed a potency rating based upon their capabilities in being able to differentiate into various other cell times for use in treatments and other developments. Based on this primary characteristic most stem cells generally fall under the totipotent or pluripotent cell rating, though various other types can also be considered stem cells for use in modern day studies:
Totipotent – in some circles also referred to as “omnipotent”, totipotent cells have the potential to form any cell type necessary based on the inherent DNA embedded for their control processes. These cells are generally found in newly formed eggs and form the basis for both embryonic and extra-embryonic development.
Pluripotent – Cells derived directly from the initial totipotent cells, these cells also hold the potential to form virtually all cell structures before they have differentiated into specialized systems.
Multipotent – The next stage following pluripotent cells, multipotent cells can form a variety of different cellular structures however are generally limited to closely related cell systems due to their partial differentiation.
Oligopotent – Highly limited in their flexibility of use, oligopotent stem cells can only be used in very similar, closely related systems that will have limited differences from their initially intended system.
Unipotent – Highly differentiated, unipotent stem cells maintain the ability to only form one particular type of cell, however unlike other cells that do not fall under the stem cell range (such as muscle cells) these cells have the ability to self-replicate and develop renewing tissues or other systems.
The primary difference separating each of these classifications of stem cells from other non-stem cells found within a body is the fact that each of these cells has the ability to repair or regenerate tissues and system components that other cell types cannot. Depending on the actual stage in terms of levels of differentiation the cells have gone through, however, the actual usefulness of each particular stem cell can be either great or highly limited and severely affect its viability as a treatment cell in terms of medical application. Nevertheless each form of stem cells is being studied and explored in order to develop various different treatments and cures for diseases as well as explore useful applications of adult stem cells that can be harvested and used with limited ethical concern that affects most fetal stem cell usage today.
Stem Cells Hereditary Diseases
Hereditary diseases have long been a problem plaguing the medical profession due to the inherent difficulties associated with combating both their development in a growing organism as well as the potential for them to be passed on from parent to offspring. The advent and subsequent development of stem cells in the medical world has opened up a realm of new possibilities for many researchers, however, both in the form of germ line therapy and somatic gene therapy.
Germ Line Therapy
The essence of germ line therapy comes from modifying actual heritable traits present in germ cells (such as sperm and egg gametes) that can be passed down from one generation to the next. This form of treatment has been seen as highly advantageous in many ways over other treatments as it can both effectively eliminate a hereditary disease before it even begins to develop in an individual while at the same time prevent the disease from being transmitted to additional offspring.
Unfortunately due to the fact that this particular type of treatment involves the direct modification of gamete cells it has met substantial opposition to counter its support from a number of people worldwide as it effectively modifies pre-set standard DNA chains in order to eliminate undesirable attributes. Further, due to the fact that any modification of a germ cell in this sense would require an in-depth understanding of the target subject’s genome and what each individual aspect corresponds to this can make pinpointing and eliminating specific genetic code challenging at best.
Somatic Cell Therapy
Unlike the heritable cells generated from germ line therapy, somatic cell therapy works to treat specific cells affected with an inherited disease without generating any heritable characteristics. Many times somatic cell therapies come in the form of modified viruses designed specifically to target key DNA lines in infected cells and eliminate the trouble zone in order to cure an ailment. Alternatively they can also be used to generate necessary cells or tissues that would also otherwise not be present due to a hereditary problem, allowing for more immediate treatment to occur.
While somatic cell therapy has generally been much more welcomed by most social and scientific groups due to the fact it has no long-term heritable effects upon a body at the same time it is for that very reason that it has some significant drawbacks. In many cases somatic cell therapy must continue for extended periods (and sometimes indefinitely) in order to function properly due to no real change occurring within a targeted cell and a direct treatment, while effective, may never actually cure a hereditary disease from recurring due to the fact that they are generally coded into an individual’s DNA from the time of their initial conception.
Stem Cell Timeline
Although stem cells have generally been considered a modern development the actual history leading up to stem cell development spans centuries, from the 1800s to modern-day scientific application:
Mid-1800s – Cells were first discovered as the basic building blocks of life, with some cells being noted as having the capability of producing other cells within a body.
Early 1900s – During attempts to fertilize mammal eggs outside of parental bodies it was discovered that some cells had the capability to produce blood and generate additional cells for fetal development.
1968 – The first successful bone marrow transplant was performed in order to treat two siblings suffering from combined immunodeficiency syndrome, a landmark breakthrough in adapting one individual’s cells to a foreign body.
1978 – As a result of further investigation into human cell development and application in science stem cells were first discovered in human fetal cord blood.
1981 – The first in vitro (test tube) stem cell line was developed from laboratory mice, providing a basis for further studies into other cell development trends in other mammals
1988 – Embryonic stem cell lines were first successfully derived from a hamster, leading researchers further down the line towards modern-day developments by broadening the scope of focus for cell sources.
1995 – The first primate embryonic stem cell lines were developed, allowing for a more realistic study of cells that develop close to human-like characteristics.
1997 – Two major discoveries took place this year, both in the form of successfully cloning a sheep from ovine stem cells (proving that the central DNA structure found within the stem cell structure is fully compatible to an entire living creature) as well as leukemia’s origin being discovered as residing in hematopoietic stem cells – potentially hinting at an actual cancer stem cell for further study towards combating cancer development.
1998 – Thompson at the University of Wisconsin successfully cultivated the first human embryonic stem cell line, sparking the first major ethical debate in terms of stem cell research and both its application to as well as effect upon human beings.
1999 and 2000 – Scientists discovered that by manipulating various tissues from adult mice they could generate different types of cells and stimulate growth, giving birth to the study of what is now commonly known as “adult stem cells” and both their collection from and application to fully developed adults (a much more ethically acceptable practice to most individuals).
Why Do Stem Cells Differentiate
Stem cells are in essence the primary building blocks of our bodies. First developed when we are forming in an embryotic state, stem cells are used to form the basic structures of our body (including the skeletal, nervous and various tissue systems that we need for our very survival). While in the initial stages of our development these cells are highly versatile and can be used for any number of different functions. This allows for one cell to easily replace another if that cell should be having problems, helping to ensure the healthy development of a child before it is born.
As our bodies develop, however, stem cells must specialize in certain tasks in order to allow our body’s different systems to both function independently of one another while still interlinking and working together as a single organism. This means that the previously highly flexible stem cells that could be used for any number of bone, tissue or nerve growth must focus on one particular area and differentiate themselves from other stem cells in order to be more easily used in that area later on should additional cell growth be necessary.
These cells can further be found differentiating even further as human being grow and develop themselves through childhood and adolescence. Puberty is a primary changing point where a number of new systems are established and in order to meet the body’s structural demands stem cells must work appropriately to handle those. This leads stem cells to focus or differentiate more and close off some developmental pathways while opening up others for our body’s use.
Although stem cells may become more and more specialized as we grow older this does not mean that they cannot be used in various different ways effectively with enough propagation and genetic coding. Recent scientific discoveries are finding new ways to “bend” stem cells harvested from adult bodies into new genetic structures to aid with tissue, bone, cartilage and nerve regrowth that the stem cell may not be involved with normally (such as recent reports from Japan of stem cells being able to be harvested from developing wisdom teeth for usage in various different areas of the body).
Unfortunately no matter how much scientists may “push” stem cells harvested from adults in a certain way there is only so much that they can do and the stem cells simply will not be effective in generating any and all body systems imaginable. This is due to the fact that the previous differentiation the stem cells have undergone during the body’s development (with either partial or full specialization towards a specific system or structure) in order to allow the cell to perform its job more efficiently and thoroughly simply makes them unsuitable for most usage far outside of their pre-determined realm. While this does not mean that they have no flexibility in usage outside of their normal areas the farther and more “foreign” the system or structure is to the originally specialized system or structure then the less likely the stem cell is to effectively form appropriately.
How Do Stem Cells Cure Diseases
In order to understand how stem cells have the potential to cure diseases it is important to first fully understand what stem cells are and how they relate to our bodies. First formed in an embryotic state, stem cells are cellular structures that are virtually a genetic blank slate – meaning that they can differentiate and change themselves to form tissue, bone or nerve cells as needed by a body during development. As we grow older and develop these cells specialize in specific tasks, forming our skin, skeletal structure, organs, nervous system and brain. Even our blood is formed through developing stem cells and generated through their specialization to that task.
As our body develops further some of these stem cells then compartmentalize into specific body areas to be used for cellular regeneration later on as needed. While these stem cells are generally less flexible than their embryotic counterparts due to the fact that they have generally partially specialized to a particular task (such as knee stem cells generally being best suited for knee bone, cartilage or fat generation) they are still flexible enough to be used by the body for whatever specific task may be needed at any given time.
Because of the flexibility and potential for stem cells to be used in so many different ways many scientists believe that they hold the cure for a number of different diseases affecting people today. As diseases generally target specific cellular structures and in many cases render them useless (such as the thalamus’ production of dopamine being rendered inactive in the case of Parkinson’s Disease) researchers feel that harvesting stem cells and “programming” them with the genetic code necessary to develop into a healthy version of the affected area and then re-injecting them into the body could effectively be used to treat or cure a number of different diseases, disabilities or even traumas such as spinal cord injuries that until now have been considered untreatable.
The primary limiting factors facing most stem cell applications in the treatment of human diseases lie in both the source of the stem cells as well as the actual usability of the end product down the line. Embryotic stem cells, for instance, have the highest ability to conform to any existing body structure and be effective in treatments, however the harvesting of these cells would generally mean the destruction of a human embryo for the sake of the stem cells’ harvesting and is therefore considered highly unethical (and is even banned in most countries by government mandate). Alternatively pre-existing stem cells harvested from adults could also be used, however these have much less flexibility in terms of usefulness and if taken from donors may also run the risk of the body rejecting the cell outright as a foreign organism.
Still, scientific advancements in terms of stem cell development and application to the treatment of diseases are progressing rapidly and many believe that many of the difficulties currently facing stem cell usage will be overcome in a few short years, allowing for the successful treatment and possible cure of many ailments.
Stem Cells Teeth
Teeth, or more specifically wisdom teeth that are generally removed by most dentists around the age of 20, have recently been determined to have the potential to be used as stem cell sources for development into various tissues and bone structures by Japanese researchers. Although the stem cells harvested from these teeth may not have the flexibility of some other stem cells (such as embryotic stem cells) they do allow for a convenient, ready source of stem cells for treatment and usage by medical professionals worldwide without the ethical stigma normally associated with stem cell usage.
Found to be viably harvestable by either utilizing a biological “pulp” formed from ground wisdom teeth or harvested directly from the teeth that have not been removed the mysenchymal stem cells have proven effective in generating a number of different biological structures, however pushing the envelope of their flexibility has been difficult due to the fact that the stem cells are harvested from pre-determined anatomical structures to begin with. This means that utilizing these stem cells in brain nerve regeneration, for example, may not yield the most desirable results, however facial bone regrowth may be a high probability.
One of the areas in particular that these new stem cells have shown excellent results in is the regrowth of teeth that may have been lost or damaged. Harvesting the stem cells and then programming them to regrow certain calcium structures has allowed researchers to actually replace lost teeth with real, natural structures, something that has been only theoretical in previous years and is a developmental breakthrough for those in the dentistry field.
What this means for most individuals is that the use of dentures and other false teeth may soon go by the wayside as real teeth can be simply regrown rather than lost forever. Combined with proper dental hygiene as well as many other government-driven oral protective measures (such as fluoride being added to drinking water and toothpaste to help fight tooth decay) the current “nexter” generation (those who are the offspring of the Baby Boomers) may be the first generation to have the majority of the people go from birth to death without losing one tooth to bad hygiene (though of course physical trauma is still a major concern for many and the primary result of lost teeth for professional athletes such as hockey players).
Currently studies are continuing into the actual usefulness the new stem cells may have in helping to rebuild different body structures and scientists are hopeful that they will be able to see actual human application in a few years. While this may seem quite a long time for most people a time frame of a few years from discovery to actual human usage is quite short, especially in terms of stem cell development. Still, since these cells are easily harvested from what is most often discarded material (as wisdom teeth are commonly simply disposed of after removal) as well as able to be directly harvested most researchers feel that there will be little restrictions placed on their exploration of the usage and patients should see real-world usage in under a decade.
Stem Cells Parkinson’s Disease
Parkinson’s Disease is an unfortunately relatively common disorder developed by individuals, with over one million reported cases existing within the United States alone. This highly debilitating disease starts as a small tremor in the hands or feet and eventually spreads throughout the entire body, causing many afflicted to lose the ability to walk or use their arms and hands effectively. Though there are a number of different treatments currently available there is no known cure for Parkinson’s Disease at this time.
Caused by neurological degeneration where dopamine generating cells in the sector of the brain known as the thalamus stop functioning the resulting dopamine deficiency causes the electrical synapses that drive all motor functions to miss-fire. In short this effectively means that an individual will slowly lose conscious control of their body’s motor functions, and while they may be able to maintain some semblance of muscle usage over time the progressive nature of the disease generally means that the conscious ability to control movement will become less and less over the course of a few years (or decades at most).
Because researchers known the cause of the disease as well as various hypothetical ways to treat the condition they feel that Parkinson’s Disease is a prime candidate for stem cell research that may one day lead to the actual curing of the condition. For instance, it is believed that by cultivating dopamine-generating brain cells and injecting into the thalamus would allow the stem cells to replace the currently defective cells causing the disease’s progression and potentially result in a quick, effective treatment and possible outright cure for the condition.
Unfortunately due to the limited research that has been done into stem cells as of this time because of various government regulations and other restrictions facing their exploration around the world stem cells are still far from being effectively used in actual human application and many believe that it will still be years before scientists will reach the stage where actual human trials will be viable. While this may be terrible news for many sufferers at the same time it is an unfortunate necessity due to the potential for stem cells to do more damage than good if injected into the brain without proper cellular preparation as well as a comprehensive understanding of how they will react both in the short- and long-term after being injected.
One of the primary concerns involved with stem cells is their potential to continue to develop unchecked into various forms of cancer. While this likelihood is still theoretical due to the limited amount of practical application that has been done in the past it is still a possibility and if any human applications are attempted before research has reached the appropriate level it could easily trade one disease for another. Still, most researchers anticipate that within the decade they will see some positive results from their studies, and if so then Parkinson’s along with a number of other ailments such as multiple sclerosis, ALS, Alzheimer’s or even spinal cord injuries.